JPH0459970B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing copper alloy terminal lead wires used for resistors, capacitors, silicon or germanium semiconductor devices, etc., and in particular, the present invention relates to a method for manufacturing copper alloy terminal lead wires used for resistors, capacitors, silicon or germanium semiconductor devices, etc. In particular, the present invention relates to a method for manufacturing copper alloy terminal lead wires used for resistors, capacitors, silicon or germanium semiconductor devices, etc. The present invention relates to a method for manufacturing a terminal lead wire for electronic device parts that maintains excellent mechanical properties even when subjected to molding processing or heat treated together with element parts. (Prior Art) Blunt copper wire, heat-resistant copper alloy wire, etc. are used for terminal lead wires for electronic device parts. These lead wires are used as terminal lead wires for components, so
One end of the lead wire is compressed and molded (hereinafter referred to as header processing) and then cut into a fixed length using high-speed automated equipment for mass production. Therefore, if the wire is hard, it will be difficult to process the header, causing cracks during the molding process and hindering the mass production process. Therefore, it is necessary to temper the hardness of the wire depending on the application. Further, during the manufacturing process of electronic device parts, when or after the lead wire is attached to the element component, the lead wire is subjected to various heat treatments and unavoidable bending stress, so that the lead wire is softened and bent. For example, lead wires used in resistors and capacitors undergo heat treatment at approximately 250°C during manufacturing processes such as brazing, molding, painting, and stabilization. or,
In the case of semiconductor devices, the soldered joint between the device component and the terminal lead wire is heat treated at 300° C. to 400° C. for about 10 minutes, and then the soldered portion is molded with a synthetic resin material. In particular, if the lead wire is made of blunt copper, it has high electrical conductivity and thermal conductivity, but heat treatment at around 200°C recrystallizes and softens it, reducing its bending strength, making it difficult to move element parts to the next process. The lead wire is bent during the process of plating inside or on top of the copper wire. Therefore, blunt copper wire cannot be used when undergoing high-temperature heat treatment. Automated mass production methods are used to manufacture these electronic device parts, so if the terminal lead wires become softened and bent, it is no longer possible to manually sort out or correct the bends, which will interfere with automation. This also causes trouble when mounting element parts on a printed circuit board. For this reason, heat-resistant copper alloy wires containing a small amount of elements such as Ag, Sn, and In are used as lead wires that undergo heat treatment at high temperatures. After cold wire drawing, the alloy wire is subjected to continuous softening or batch softening to improve the hardness of the wire, but variations in header workability and bending strength after high-temperature heat treatment have yet to be resolved. Therefore, even if the characteristics of the element parts are highly reliable, there remains a problem in automation due to defects in the terminal lead wires. (Problem to be solved by the invention) The characteristics that lead wires that are suitable for the automatic production system of electronic device parts must have are good header workability and heat resistance against process heat treatment (400°C x 10 minutes). It has electrical conductivity of 95% or more, good thermal conductivity for heat radiation, and strong bending resistance against bending stress. Regarding these required characteristics, it is preferable to use a heat-resistant and highly conductive copper alloy, and the alloy composition is Ag, Sn, In, Pb,
Bi, Cr, Co, Ni, Fe, Zr, Se, Te, Hf, B,
0.02 to 0.02 or more of one or more elements such as Ti and P
A copper alloy wire with addition in the range of 0.2 Wt% will be used. As for wire rods, there is a mutually contradictory relationship in that if the wire rod is provided with bending resistance, the wire rod becomes hard, which causes a problem in header workability, and when the wire rod is made soft, the bending resistance decreases. An object of the present invention is to solve this problem and provide a more stable manufacturing method for the copper alloy wire so that the wire has good hardness and bending resistance. (Means for Solving the Invention) As a result of further investigation into a heating method for wire rods that satisfies the above-mentioned required characteristics, the present inventors found that the tensile strength value of the copper alloy wire rods before heat treatment was 27 to 27. 35
The ^present invention was completed by discovering that if it is tempered so that the elongation value is in the range of 7 to 32%, it has both properties of header workability and bending resistance. It is. That is, the structure of the present invention is that after cold drawing a copper alloy rough wire and completely annealing it, the area reduction rate is 60 to 90.
%, and after completely annealing the wire again, cold wire drawing is performed to reduce the area of the wire in the range of 2 to 20%. The details of the present invention will be further explained below. The copper alloy wire used in the present invention is made of Cu as a base material, and includes Ag, Sn, In, Pb, Bi, Cr, Co, etc.
One or more elements such as Ni, Fe, Zr, Se, Te, Hf, B, Ti, P, etc. are added to Cu at 0.02~
It has an alloy composition in which it is added in a range of 0.2Wt%. In the present invention, after drawing a copper alloy rough wire,
The wire rod is firstly annealed and drawn again with an area reduction of 60 to 90%, and then the wire is secondarily annealed and drawn with an area reduction of 2 to 20%, resulting in improved mechanical properties. It can be tempered into wire rods with tensile strength, 27~35Kg/ ^mm2 and elongation, and 7~32%. In the above, after the first annealing, the area reduction rate is 60 to 90%.
The wire drawing process is performed within the range of 60% because if the area reduction rate is less than 60%, the resulting copper alloy wire will not be hardened, and the lead wire attached to the element part will not be able to be used in the actual production process.
This is because the lead wires are bent in various steps after undergoing heat treatment at 400°C for 10 minutes. On the other hand, if it exceeds 90%, the obtained copper alloy wire becomes too hard, which makes the header processing of the terminal lead wire poor and also causes cracks in the header processing portion, which is not preferable. Next, after secondary annealing, wire drawing is performed with an area reduction rate of 2 to 20%, because if the area reduction rate is less than 2%, the resulting copper alloy wire will not be hardened and will not be attached to the element parts. This is because the lead wires undergo heat treatment at 400°C for 10 minutes during the actual production process, and the lead wires are bent in various steps. On the other hand, if it exceeds 20%, the resulting copper alloy wire becomes too hard, which deteriorates the header workability of the terminal lead wire and also causes cracks in the header processed portion, which is not preferable. (Examples) Next, the present invention will be explained in more detail with reference to Examples, Comparative Examples, and Reference Examples, but the present invention is not limited only to these Examples. As shown in Tables 1 and 2, Cu−
Three types of heat-resistant and highly conductive copper alloy rough drawn wires, 0.1Ag, Cu-0.05Sn, and Cu-0.131n, were manufactured, and after each was subjected to cold wire drawing, the former was In the case of 400℃ x 3 hours, in the latter case 380℃ x 3
As batch annealing for several hours, the wire diameter was 0.8mm by drawing with the area reduction rate shown in Tables 1 and 2.
Finished as a φ wire rod. Then, the wire rod was subjected to header processing using a high-speed automatic header processing machine, and the suitability of the header processing and whether or not cracks were produced in the header processing portion were investigated. Furthermore, lead wires are attached to the electronic device element parts and heat treated at 400℃ for 10 minutes during the actual production process.
It was investigated whether the lead wire would be subjected to bending stress during the process and cause problems in production. These results are also listed in Tables 1 and 2. As can be seen from the results, in Examples 1 to 27, the header workability, that is, the softness of the wire rod, was properly tempered, so they showed good results, and the bending resistance after heat treatment was also better than that of the wire rod. Since the hardness of the wire is appropriately tempered, it is suitable for the production process of element parts, and the lead wire is not bent. In Comparative Examples 28 to 42, the softness and hardness of the wire rods were not tempered, so even if the header workability was good, the bending resistance after heat treatment was unfavorable.
In addition, it can be seen that, contrary to the above, neither of them can be tempered into a suitable wire material. In Reference Examples 43 to 51, the wire rods are refined only by secondary annealing, that is, without primary annealing, so some of them satisfy both header workability and bending resistance after heat treatment; Since one of them may be missing, the refining range in the wire refining method is limited. Next, although batch annealing was used as the annealing in this example, it goes without saying that it can be performed using a continuous wire drawing and softening apparatus. (Effects of the Invention) The lead wire manufactured by the present invention not only has excellent reliability in bending strength against high-temperature heat treatment, but also has excellent mechanical properties, high electrical conductivity, good thermal conductivity, and excellent header processing. Semiconductor elements such as silicon and germanium, which have excellent properties, are easy to manufacture, and are inexpensive, are used for automatic production.
It is extremely effective as a terminal lead wire for electronic equipment parts such as resistors, capacitors, switches, connectors, and coil parts.

【table】

[Table] Those without. × mark: Items that have difficulty bending during the actual process.

【table】

【table】

Claims (1)

[Claims] 1 After completely annealing the copper alloy wire, the area reduction rate is 60~
A terminal lead for electronic device parts, characterized in that the wire is cold drawn to a range of 90%, the wire is completely annealed again, and then the wire is cold drawn to a reduction of area of 2 to 20%. Method of manufacturing wire.